Motor vehicle suspension performs two functions: helping to keep the vehicle safely on the road under all circumstances (braking, cornering, different road surfaces, etc.) and ensuring comfortable conditions for passengers in an insulated passenger compartment (noise, vibration, shocks, etc.).
These goals are generally at odds, and so require compromise solutions, in particular between the stiffness of the springs and the compression ratio of the shock absorbers generally making up the motor vehicle suspension members on each wheel.
In order to monitor the state of a suspension system, with a view to estimating the appropriate time to change same by identifying a critical degree of degradation due to ageing of the components or faults that worsen over time, the suspension may be tested manually during a road worthiness test, although such solutions are dependent on the degree of expertise of the operative, or a test bench may be used to provide objective results.
These benches test the effectiveness of the suspension by measuring adhesion values, in particular using the measurement method provided by the European Shock Absorber Manufacturers Association (EUSAMA).
However, the measurements provided by such test benches are not precise enough to determine the state of a suspension system in terms of full-scale behaviour in a real context.